Due to multifarious applications of small-scale liquid transport, there had been different proposals on how such liquid transport could be achieved. Despite much effort in this arena, there had been many difficulties which, in the past, were not able to address, or at least not adequately. For example, the speed or motion of liquid transport was usually slow; the transport distance was relatively limited; and the flow direction was not controllable or least not well controlled due to unwanted pinning of contact lines by defects on a surface of the liquid transport system.
The present invention seeks to address the above problems, or at least to provide an alternative to the public.